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Indian Journal of Ophthalmology May 2024Slit lamp biomicroscope is the right hand of an Ophthalmologist. Even though precise, its bulky design and complex working process are limiting constraints, making it...
Slit lamp biomicroscope is the right hand of an Ophthalmologist. Even though precise, its bulky design and complex working process are limiting constraints, making it difficult for screening at outreach camps, which are an integral part of this field for the purpose of eliminating needless blindness. The torchlight is the main tool used for screening. Recently, the integration of smartphones with instruments and the digitization of slit lamp has been explored, to provide simple and easy hacks. By bringing the slit of the slit lamp to traditional torchlight, we have created "The Slitscope". It combines the best of both worlds as a simple innovative do-it-yourself novel technique for precise cataract screening. It is especially useful in peripheral centers, vision centers, and outreach camps. We present two prototypes which can also be 3D printed.
Topics: Humans; Slit Lamp Microscopy; Equipment Design; Cataract; Vision Screening; Smartphone
PubMed: 38189430
DOI: 10.4103/IJO.IJO_1589_23 -
Indian Journal of Ophthalmology Jul 2023The optimal method of treatment for a child depends on the patient's age at the time of diagnosis, the onset and type of amblyopia, and the degree of compliance... (Review)
Review
The optimal method of treatment for a child depends on the patient's age at the time of diagnosis, the onset and type of amblyopia, and the degree of compliance attainable. In deprivation amblyopia, the cause of visual impairment (e.g., cataract, ptosis) needs to be treated first, and then the disorder can be treated such as other types of amblyopia. Anisometropic amblyopia needs glasses first. In strabismic amblyopia, conventionally amblyopia should be treated first, and then strabismus corrected. Correction of strabismus will have little if any effect on the amblyopia, although the timing of surgery is controversial. Best outcomes are achieved if amblyopia is treated before the age of 7 years. The earlier the treatment, the more efficacious it is. In selected cases of bilateral amblyopia, the more defective eye must be given a competitive advantage over the comparatively good eye. Glasses alone can work when a refractive component is present, but occlusion might make the glasses work faster. The gold standard therapy for amblyopia remains occlusion of the better eye although penalization is also evidenced to achieve equal results. Pharmacotherapy has been shown to achieve suboptimal outcomes. Newer monocular and binocular therapies based on neural tasks and games are adjuncts to patching and can also be used in adults.
Topics: Child; Adult; Humans; Amblyopia; Visual Acuity; Sensory Deprivation; Strabismus; Refraction, Ocular; Treatment Outcome
PubMed: 37417105
DOI: 10.4103/IJO.IJO_338_23 -
American Journal of Ophthalmology Sep 2023To investigate myopia control efficacy in children who continued wearing spectacle lenses with highly aspherical lenslets (HAL) or switched from spectacle lenses with... (Randomized Controlled Trial)
Randomized Controlled Trial
PURPOSE
To investigate myopia control efficacy in children who continued wearing spectacle lenses with highly aspherical lenslets (HAL) or switched from spectacle lenses with slightly aspherical lenslets (SAL) and single-vision spectacle lenses (SVL) to HAL for 1 year after a 2-year myopia control trial.
DESIGN
This was a 1-year extension of a randomized clinical trial.
METHODS
Of 54 children who had worn HAL for 2 years, 52 continued wearing HAL (HAL1 group), and of the 53 and 51 children who had originally worn SAL or SVL, 51 and 48 switched to wearing HAL (HAL2 and HAL3 groups) in year 3, respectively. A new SVL (nSVL) group of 56 children was recruited, matched for age, sex, cycloplegic spherical equivalent refraction (SER), and axial length (AL) of the HAL3 group at extension baseline, and used for a comparison of third-year changes. SER and AL were measured every 6 months in year 3.
RESULTS
During year 3, the mean (SE) myopia progression in the nSVL group was -0.56 (0.05) diopters (D). Compared with nSVL, the changes in SER were less in HAL1 (-0.38 [0.05] D, P = .02), HAL2 (-0.36 [0.06] D, P = .01), and HAL3 (-0.33 [0.06] D, P = .005). The mean (SE) AL elongation in the nSVL group was 0.28 (0.02) mm. Compared with nSVL, the elongation in AL was less in the HAL1 (0.17 [0.02] mm, P < .001), HAL2 (0.18 [0.02] mm, P < .001), and HAL3 (0.14 [0.02] mm, P < .001) groups. Myopia progression and axial elongation were comparable in all 3 HAL groups (all P > .05) in year 3.
CONCLUSIONS
Myopia control efficacy has remained in children who wore HAL in the previous 2 years. Children who switched from SAL or SVL to HAL in year 3 had slower myopia progression and axial elongation than that in the control group.
Topics: Child; Humans; Follow-Up Studies; Eyeglasses; Disease Progression; Myopia; Refraction, Ocular
PubMed: 37040846
DOI: 10.1016/j.ajo.2023.03.030 -
The British Journal of Ophthalmology Nov 2023Mutations in the L/M cone opsin gene array cause abnormally high perceived retinal contrast and the development of myopia. Environmental factors may also lead to high... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Mutations in the L/M cone opsin gene array cause abnormally high perceived retinal contrast and the development of myopia. Environmental factors may also lead to high visual contrast and cause myopia. Diffusion optics technology (DOT) lenses are designed to reduce contrast signalling in the retina and slow myopia progression.
METHODS
The ontrol of Mopia Using eripheal Diffusion Lenses fficacy and afety tudy (CYPRESS, NCT03623074) is a 36-month, multicentre, randomised, controlled, double-masked trial evaluating two investigational spectacle lenses versus control lenses in myopic children aged 6-10, with a planned interim analysis at 12 months. The primary endpoints are change from baseline in axial length (AL) and spherical equivalent refraction (SER).
RESULTS
256 children (58% female; mean age at screening, 8.1 years) were dispensed spectacles. Across all groups, baseline averages were AL 24.02 mm (SD±0.77 mm), SER -2.01 D (SD±0.9 D) using manifest refraction, and SER -1.94 D (SD±1.0 D) using cycloplegic autorefraction. At 12 months, mean difference in SER progression for test 1 versus control was -0.40 D (p<0.0001), representing a 74% reduction and -0.32 D for Test 2 (p<0.0001), representing a 59% reduction. The difference in AL progression for test 1 versus control was 0.15 mm (p<0.0001) and test 2 versus control was 0.10 mm (p=0.0018).
CONCLUSION
12-month results from this ongoing trial demonstrate the safety and effectiveness of DOT spectacles for reducing myopic progression.
Topics: Child; Humans; Female; Male; Cupressus; Eyeglasses; Myopia; Refraction, Ocular; Retina
PubMed: 36126105
DOI: 10.1136/bjo-2021-321005 -
Journal of Vision Apr 2024The perceived slant of a stereoscopic surface is altered by the presence of a surrounding surface, a phenomenon termed stereo slant contrast. Previous studies have shown...
The perceived slant of a stereoscopic surface is altered by the presence of a surrounding surface, a phenomenon termed stereo slant contrast. Previous studies have shown that a slanted surround causes a fronto-parallel surface to appear slanted in the opposite direction, an instance of "bidirectional" contrast. A few studies have examined slant contrast using slanted as opposed to fronto-parallel test surfaces, and these also have shown slant contrast. Here, we use a matching method to examine slant contrast over a wide range of combinations of surround and test slants, one aim being to determine whether stereo slant contrast transfers across opposite directions of test and surround slant. We also examine the effect of the test on the perceived slant of the surround. Test slant contrast was found to be bidirectional in virtually all test-surround combinations and transferred across opposite test and surround slants, with little or no decline in magnitude as the test-surround slant difference approached the limit. There was a weak bidirectional effect of the test slant on the perceived slant of the surround. We consider how our results might be explained by four mechanisms: (a) normalization of stereo slant to vertical; (b) divisive normalization of stereo slant channels in a manner analogous to the tilt illusion; (c) interactions between center and surround disparity-gradient detectors; and (d) uncertainty in slant estimation. We conclude that the third of these (interactions between center and surround disparity-gradient detectors) is the most likely cause of stereo slant contrast.
Topics: Humans; Depth Perception; Contrast Sensitivity; Photic Stimulation; Vision, Binocular
PubMed: 38683571
DOI: 10.1167/jov.24.4.24 -
Cells Aug 2023Age-related macular degeneration (AMD) is the leading cause of vision loss and visual impairment in people over 50 years of age. In the current therapeutic landscape,... (Review)
Review
Age-related macular degeneration (AMD) is the leading cause of vision loss and visual impairment in people over 50 years of age. In the current therapeutic landscape, intravitreal anti-vascular endothelial growth factor (anti-VEGF) therapies have been central to the management of neovascular AMD (also known as wet AMD), whereas treatments for geographic atrophy have lagged behind. Several therapeutic approaches are being developed for geographic atrophy with the goal of either slowing down disease progression or reversing sight loss. Such strategies target the inflammatory pathways, complement cascade, visual cycle or neuroprotective mechanisms to slow down the degeneration. In addition, retinal implants have been tried for vision restoration and stem cell therapies for potentially a dual purpose of slowing down the degeneration and restoring visual function. In particular, therapies focusing on the complement pathway have shown promising results with the FDA approved pegcetacoplan, a complement C3 inhibitor, and avacincaptad pegol, a complement C5 inhibitor. In this review, we discuss the mechanisms of inflammation in AMD and outline the therapeutic landscapes of atrophy AMD. Improved understanding of the various pathway components and their interplay in this complex neuroinflammatory degeneration will guide the development of current and future therapeutic options, such as optogenetic therapy.
Topics: Humans; Middle Aged; Geographic Atrophy; Angiogenesis Inhibitors; Wet Macular Degeneration; Vascular Endothelial Growth Factor A; Visual Acuity; Inflammation
PubMed: 37626902
DOI: 10.3390/cells12162092 -
Survey of Ophthalmology 2024Keratoconus is an ectatic corneal disorder that causes severe vision loss. Surgical options allow us to correct, partially or totally, the induced refractive error.... (Review)
Review
Keratoconus is an ectatic corneal disorder that causes severe vision loss. Surgical options allow us to correct, partially or totally, the induced refractive error. Intracorneal ring segments (ICRS) implantation represents a minimally invasive surgical option that improves visual acuity, with a high success rate and a low overall complication rate. Corneal allogenic ICRS consists of ring segments derived from allogenic eye bank-processed donor corneas. Selective topography-guided transepithelial photorefractive or phototherapeutic keratectomy combined with CXL is another way in selected cases to improve spectacles corrected distance visual acuity. The microphotoablative remodeling of the central corneal profile is generally planned by optimizing the optical zones and minimizing tissue consumption. Phakic intraocular lens (PIOL) implant is considered in patients with stable disease and acceptable anatomical requirements. The two types of pIOLs, depending on their implantation inside the eye, are anterior chamber-pIOLs, which fixate to the anterior surface of the iris by using a polymethomethacrolate claw at the two haptics, and posterior chamber-pIOLs. In patients with both cataracts and keratoconus, the correct IOL power is difficult to obtain due to the irregular corneal shape and K values. Toric IOL is recommended, but carefully judging the topography and the possible need of subsequent keratoplasties.
Topics: Humans; Prosthesis Implantation; Keratoconus; Photosensitizing Agents; Corneal Stroma; Visual Acuity; Corneal Topography; Cross-Linking Reagents; Refraction, Ocular
PubMed: 37774800
DOI: 10.1016/j.survophthal.2023.09.005 -
European Journal of Internal Medicine Jul 2023
Topics: Humans; Renal Dialysis; Visual Acuity
PubMed: 36944566
DOI: 10.1016/j.ejim.2023.03.008